利用差示扫描量热法研究孔溶液结冰对水饱和水泥基材料低温热形变的影响  

Effect of Pore Solution Freezing on Thermal Strain of Water-Saturated Cement Based Material at Low Temperature by Differential Scanning Calorimetry

作　　者：张楠[1] 张涛[1] 廖娟[1] 霍亮[1] 蔺喜强[1] 李国友[1] 戢文占 

机构地区：[1]中国建筑股份有限公司技术中心,北京101300

出　　处：《硅酸盐学报》2015年第5期599-603,共5页Journal of The Chinese Ceramic Society

摘　　要：混凝土因在低温环境下具有优越的力学性能和耐久性,已被应用于液化天然气储藏塔外部保护层或内部接触层。但混凝土在低温环境下的热变形是一个复杂的过程。基于以前研究者所得水泥基材料超低温热形变宏观结果,采用差示扫描量热技术研究不同水灰比水饱和硬化水泥石中孔溶液的冰点,以解释热形变机理。结果表明:直径小于8 nm的孔中溶液的结冰对水泥基材料低温膨胀起主导作用;当环境最低温度低于–50℃时,水泥基材料热应变的变化和损失随水灰比增大逐渐明显。Concrete is applied to secondary or primary container of many tanks that store liquefied natural gas due to the excellent mechanical property and durability at low temperature. However, thermal strain of concrete is a complex process at low temperature. Based on the previous studies, this work was to explain thermal strain change using a thermal analysis technique in order to analyze freezing point of pore solution in water-saturated hardened cement paste with different water/cement ratios. The results indicate that the thermal expansion of cement-based materials at low temperatures becomes critical, thus freezing the pore solution with the pores of smaller than 8 nm. At < –50 ℃, the thermal strain change and the damage of cement-based material are gradually obvious when the water/cement ratio increases.

关 键 词：热分析 热应变 低温 水泥基材料 孔溶液 

分 类 号：TU528[建筑科学—建筑技术科学]